I have a 350 engine block about 1979 I just had it rebuilt but the water pump hole on the passengers leaks coolant the 2 bolts that hold the water pump are threaded but the one below is not and that is the one that leaks has any one heard of this the old block it was a dead end hole but this seem to go into the water jacket is that possible. Thanks
There are only four bolts used to attach the water pump to the block. As Steiner said the by-pass is internal on the small block, but it is external on the big block. Here is a picture of the front of the block showing the by pass hole in the block just below the water entrance into the block.
And an exploded view:
All four bolts go into the water jacket (as do all of the head bolts, and four of your intake bolts), and you (or your engine builder) need to use sealant on the threads to keep coolant from SLOWLY wicking out of the motor. If you have water pouring out I would suspect a torn gasket or a foreign object (such as the old torn gasket that wasn't scraped off) caught between the block and the water pump that prevents the pump from seating properly.